891973680402439 has 2 divisors, whose sum is σ = 891973680402440. Its totient is φ = 891973680402438.

The previous prime is 891973680402403. The next prime is 891973680402451. The reversal of 891973680402439 is 934204086379198.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 891973680402439 - 2¹¹ = 891973680400391 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (891973680402499) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 445986840201219 + 445986840201220.

It is an arithmetic number, because the mean of its divisors is an integer number (445986840201220).

Almost surely, 2^{891973680402439} is an apocalyptic number.

891973680402439 is a deficient number, since it is larger than the sum of its proper divisors (1).

891973680402439 is an equidigital number, since it uses as much as digits as its factorization.

891973680402439 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 564350976, while the sum is 73.

The spelling of 891973680402439 in words is "eight hundred ninety-one trillion, nine hundred seventy-three billion, six hundred eighty million, four hundred two thousand, four hundred thirty-nine".